Sunday, 15 November 2009

Quantum Buddhism - Buddhist Particle Physics

Partless Particles - a Logical Impossibility
The 8th century Indian Buddhist Scholar Shantideva rejected the possibility of Partless Particles:

'(93) If there is space between the partless particles of a sense power and those of its object,
How can you maintain that they have met?
But if there is no space between them, they must mix and become completely one;
In which case, what is it that meets with what?

(94) But one partless particle could never penetrate another
Because they would both be equal in size without any empty space inside.
Without penetrating, they could not mix;
And without mixing, they could not meet.

(95) To say that two partless things can meet is completely illogical. If it were possible, you would be able to detect it; So please show me an example! '

GesheKelsangGyatso adds:'All forms have parts because they are composed of particles. Some Vaibhashika and Sautrantika schools assert that the tiniest particles do not have parts because they are physically indivisible, but according to the Madhyamika school they have directional parts and so are mentally divisible. If even the smallest forms have parts, it follows that all gross forms that are composed of them also have parts.' - Ocean of Nectar p 164

Inherent existence of Partless Particles
So according to these Buddhist philosophers, a Partless Particle would be inherently existent. It would exist undetectable in splendid isolation, unable to exchange any part of itself with any other entity, or accept into itself any part of any other entity.

Such a particle would thus be incapable of taking part in any process or manifesting its existence in any way. It would be completely defined by its own nature and would be incapable of changing by undergoing any internal changes of state.

Avoiding the infinite regression
But if partless particles cannot exist, how can we avoid the infinite regress of small building-blocks being composed of even smaller building-blocks, all the way down for ever?

This infinite regression...

... doesn't happen!

Wavefunction probability distribution
The resolution of this apparent contradiction came with discoveries in quantum physics in the early twentieth century. When physicists arrived at the stage where further subdivision was no longer possible, they did indeed find numerically irreducible particles. However these particles are no longer discrete 'things', but are smeared out into a myriad of fuzzy probabilistic 'parts' - a continuum of probabilities distributed in a wave function throughout space.

The fact that the particles are no longer discrete entities is demonstrated by the double-slit experiment, where single electrons (and more recently other individual particles, including comparatively large molecules such as fullerenes,) appear to pass through two separate slits simultaneously.

Distribution of single particles fired one at a time through top slit...

Distribution of single particles fired one at a time through bottom slit...

What you would expect with both slits open...

What actually happens with both slits open...

To quote Wiki:
'The double-slit experiment has been of great interest to philosophers, because the quantum mechanical behavior it reveals has forced them to reevaluate their ideas about classical concepts such as "particles", "waves", "location", and "movement from one place to another".

In contrast to the way of conceptualizing the macroscopic world of everyday experience, attempting to describe the motion of a single photon is problematic. As Philipp Frank observes, investigating the motion of single particles through a single slit can obtain a description of the pattern of photon strikes on a target screen. However, "the pattern of fringes for two slits is not the superposition of the two patterns for single slits. Hence, there is no law of motion that would determine the trajectory of a single photon and allow us to derive the observed facts that occur when photons pass two slits." Experience in the micro world of sub-atomic particles forces us to reconceptualize some of our most commonplace ideas.'

This probabilistic behavior is logically inevitable
So, bizarre as this non-localised, two-places-at-once quantum behavior of fundamental particles may appear, we are forced to conclude that it is necessary in order to avoid two even worse logical absurdities, either...

[ii] The absurdity of an infinite regress of ever smaller components and subcomponents which can never bottom out. (If it did terminate it could only do so at the level of inherently-existing, partless fundamental monads, which brings us back to absurdity [i] )

Avoiding components having subcomponents all the way down
The infinite regress 'downwards' into infinitely deeper levels of particles, subparticles, sub-subparticles etc is avoided by sending the infinity 'sideways' into a probability cloud of an infinite number of 'possible' instances of the particle. The infinity is necessary in some form or other to avoid having a partless particle which is a 'thing in itself'.

3 comments:

Hi Dreamwriter, thanks for stopping by. I've currently got a list of about 20 topics due for posting (when I have time to write them) so there should be plenty more stuff coming, especially as the list seems to be growing faster than I can clear it.

I see from your blog you're a Tara devotee like myself. Tashi Mannox, a talented Tibetan-trained calligrapher has some fine Tara calligraphy at Inkessential including Tara's mantra and seed syllable.